Table 1.

The modified Romberg tests of Standing Balance on Firm and Compliant Support Surfaces was used to identify the presence of VSCD (Shumway-Cook and Horak 1986; Agrawal et al. 2013). The modified Romberg Test examines ability to stand unassisted using 4 test conditions designed specifically to evaluate the different sensory inputs that contribute to balance—vestibular system input, vision, and proprioception (Agrawal et al. 2011). A time to fall < 20 seconds on the Romberg 4 test (standing on foam surface with eyes closed) in the absence of falling during conditions 1–3 is defined as evidence of VSCD.

Romberg condition	1 Stand with eyes open on firm surface	2 Stand with eyes closed on firm surface	3 Stand on foam mat with eyes open	4 Stand on foam mat with eyes closed	Diagnosis of VSCD: Failing the Romberg 4 condition in the absence of failing conditions 1–3
Sensory input	Visual, propioceptive & vestibular	Propioceptive & vestibular mainly	Visual & vestibular	Vestibular only